1. Field of the Invention
The present invention relates to warming devices and methods, and in particular, to warming a seat using an air-activated, exothermic reaction.
2. Description of Related Art
Many athletic events are performed at relatively cold temperatures, either outdoors or in an open-air stadium. The spectators will be relatively sedentary and can easily become chilled when sitting on stadium seats or simple bench-style bleachers. Often these seating arrangements will have a hard plastic or metal seat that tends to remain cold or even draw away body heat. To combat this problem, spectators will dress warmly and use blankets and the like, in order to try and retain their body heat.
Portable cushions have been placed on stadium seats for comfort and for insulation from the cold. However, cushions tend to be bulky, are easily misplaced or lost, and are inconvenient to carry back and forth. Also, vendors cannot easily travel through a stadium carrying stacks of cushions for immediate sale to spectators. Moreover, once purchased, portable cushions must be periodically cleaned and handled with care if one wishes to use the cushion repeatedly.
In addition, some stadium chairs have seats that swing up when the seated person rises. A cushion can prevent the seat from fully swinging and therefore impede movement in the vicinity of the chair. This problem can be exacerbated if the cushion is secured to the seat by straps or other mechanisms that interfere with the swinging motion of the seat. On the other hand, if unsecured, the cushion can slip and fall behind the chair, becoming difficult to retrieve.
A known heat pack uses a mixture of iron powder, water, activated charcoal, vermiculite, and salt. The iron powder is oxidized (rusts) in an exothermic reaction. Air and water are necessary for the reaction to proceed, but only the water is provided in the mixture. For this reason, the mixture is stored in an air permeable envelope that is then, in turn, sealed in a relatively air impermeable bag. When the envelope containing the mixture is removed from the bag, air can reach the mixture and start the exothermic reaction. The vermiculite and activated carbon are useful for storing and releasing water to accommodate the reaction. The activated carbon is also useful in storing and releasing the salt catalyst, as well as conducting and dispersing the heat generated by the exothermic reaction.
See also U.S. Pat. Nos. 1,613,120; 1,953,513; 3,301,250; 3,976,049; 3,980,070; 4,106,478; 4,604,987; 5,398,667; 5,545,198; 5,833,309; 7,438,356; and D329,957.